1. Technical Field
Embodiments of the present invention relate to a display. More particularly, embodiments of the present invention relate to a reflective display and the front-light module thereof.
2. Description of Related Art
A typical electronic book reader, which is configured to show colored images employs a color filter disposed on a reflective display panel. The reflective display panel includes a plurality of microcapsules having black and white particles. The color filter includes a plurality of sub-pixel regions having various colors, such as red, green and blue. By controlling the gray scale variation of the microcapsules under different sub-pixel regions, the electronic book reader can thereby show the colored images.
To display the colored images, the sub-pixel region of the color filter absorbs the light in a particular range of wavelength, and only allows the light in the other range of wavelength to propagate therethrough. In the light propagation, the ambient light has to travel back and forth through the color filter twice. Therefore, the use efficiency of the optical energy is significantly reduced. Under this circumstance, the electronic book reader of showing colored images normally looks darker than that of showing monochrome images. In this regard, the electronic book reader requires the front-light module to improve the brightness of the shown image.
However, even though the front-light module improves the brightness of the image, the contrast ratio and the color saturation of the image need further improvements.